The pipe organ of the Cathedral of Our Lady of the Angels was commissioned from Dobson Pipe Organ Builders, Ltd., of Lake City, Iowa. According to one authority, it is the 89th largest pipe organ in North America and the 143rd largest in the world.

Lynn A. Dobson, owner and president of the company, collaborated with Cathedral architect Rafael Moneo in the visual design of the organ. It needed to be to a scale that complemented the immense space of the nave and sanctuary. The top of the organ case is about eighty-five feet from the floor. "For an organ builder in America," Dobson explains, "that is almost unheard of to have this kind of height."

The massive organ, with one hundred and five stops and a total of six thousand nineteen pipes, includes vintage pipes from the organ in the Cathedral of St. Vibiana. The original organ was built in 1929 by the Wangerin Organ Company of Milwaukee and rebuilt by Austin Organs, Inc., in 1988.

The new organ utilizes slider chests with electric pulldowns for all manual divisions except the Solo and Pedal, which have electro-pneumatic action. These divisions are conceived of in the spirit of Isnard's 1772 Resonance division at St. Maximin: the Solo is a division of powerful voices, many of which are made playable in the Pedal, which has few independent voices of its own.

The organ is controlled from a moveable console that has four keyboards, or "manuals". Unlike older organs, it uses a computerized system to connect the keys to the valves under each pipe. The system uses a cable of only six wires to connect the console to the organ.

The front pipes are made of burnished 83% tin. "This is the largest facade in the United States made of polished tin," Dobson says. In addition to the large vertical pipes, there are horizontal trumpet pipes, some as long as sixteen feet, which also are the largest of their kind in the United States. The biggest pipe inside the organ is twenty-four inches square and is made of wood. While many of the larger pipes are made of wood, the majority of them are made of alloys of tin and lead. They are arranged in six divisions, Great, Swell, Positive, Solo, Fanfare and Pedal.

The forty-two ton organ is supported on a steel structure built into the wall. In the Cathedral basement are three blowers totaling twenty-seven horsepower, which supply the organ with wind pressure ranging from five inches to twenty inches water column. A twenty inch wind pressure is very high for an organ. "The reason for such a high pressure is that the Cathedral itself is so large that to generate enough sound to fill the room adequately, we had to go with higher wind pressure," Dobson explains.

The organ is encased in solid cherry wood, unusual in that most organ cases are built out of less expensive lumber, such as oak, or in Europe, painted pine. "It must be the biggest cherry organ case in the world," Dobson exclaims. Although the type of wood has little to do with sound quality, Moneo's design called for cherry woodwork throughout the Cathedral.

Dobson's company was chosen to build an "eclectic" organ, one that could as easily play different styles of music, from the 1500s to the present day. They are experts in the history of organ building from all different periods and understand the requirements the various musical styles make of the organ. Dobson has taken their knowledge of each period and has blended it into a new style of organ, allowing the Cathedral instrument to sound convincing in various musical styles. "We've made a new organ for a new Church," he declares.

To ensure the instrument's success in the vast nave, the voicing and tonal finishing of the organ was performed in the Cathedral. The process, which took approximately six months, was carried out by Dobson personnel under the direction of Lynn Dobson and John Panning, the firm's tonal director, in consultation with Frank Brownstead, Director of the Archdiocesan Music Office and Manuel Rosales, president of Rosales Organ Builders and technical consultant for the project.

The power of the organ makes the room vibrate enabling the assembly to not only hear the music, but also feel it, making the experience all the more powerful, emotionally, as well as physically.

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